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    <div class="sect1" lang="en" xml:lang="en">
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          <div>
            <h2 class="title" style="clear: both"><a id="envset_flags"></a>DB_ENV-&gt;set_flags()</h2>
          </div>
        </div>
      </div>
      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;set_flags(DB_ENV *dbenv, u_int32_t flags, int onoff);  </pre>
      <p>
        Configure a database environment.
    </p>
      <p>
         The database environment's flag values may also be configured
         using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.  The syntax of the entry
         in that file is a single line with the string "set_flags", one or
         more whitespace characters, and the method flag parameter as a
         string, and optionally one or more whitespace characters, and the
         string "on" or "off".  If the optional string is omitted, the
         default is "on"; for example, "set_flags DB_TXN_NOSYNC" or
         "set_flags DB_TXN_NOSYNC on". Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read
         when the database environment is opened, it will silently overrule
         configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;set_flags()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp52049216"></a>Parameters</h3>
            </div>
          </div>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp52048112"></a>flags</h4>
              </div>
            </div>
          </div>
          <p>
                          The <span class="bold"><strong>flags</strong></span> parameter must be set by
                          bitwise inclusively <span class="bold"><strong>OR</strong></span>'ing together
                          one or more of the following values:
                     </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p><a id="envset_flags_DB_AUTO_COMMIT"></a>
                  <code class="literal">DB_AUTO_COMMIT</code>
            </p>
                <p>
                 If set, <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a>  handle
                 operations for which no explicit transaction handle was specified, and
                 which modify databases in the database environment, will be
                 automatically enclosed within a transaction.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with this flag only affects the specified 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle (and any other
                 Berkeley DB handles opened within the scope of that handle). For
                 consistent behavior across the environment, all 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in the
                 environment must either set this flag
                 or the flag should be specified in the 
                 <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 This flag may be used to configure Berkeley DB at any time during the life
                 of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_CDB_ALLDB"></a>
                  <code class="literal">DB_CDB_ALLDB</code>
            </p>
                <p>
                 If set, Berkeley DB Concurrent Data Store applications will perform
                 locking on an environment-wide basis rather than on a per-database
                 basis.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_CDB_ALLDB flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_CDB_ALLDB flag or the flag
                 should be specified in the 
                 <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_CDB_ALLDB flag may be used to configure Berkeley DB only before
                 the <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>  method
                 is called.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_DIRECT_DB"></a>
                  <code class="literal">DB_DIRECT_DB</code>
            </p>
                <p>
                 Turn off system buffering of Berkeley DB database files to avoid
                 double caching.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with
                 the DB_DIRECT_DB flag only affects the specified 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> handle (and any other
                 Berkeley DB handles opened within the scope of that
                 handle). For consistent behavior across the environment,
                 all <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened
                 in the environment must either set the DB_DIRECT_DB flag
                 or the flag should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a>
                 configuration file.
            </p>
                <p>
                 The DB_DIRECT_DB flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_HOTBACKUP_IN_PROGRESS"></a>
                  <code class="literal">DB_HOTBACKUP_IN_PROGRESS</code>
             </p>
                <p>
	          Set this flag prior to creating a
	          hot backup of a database environment.
	          If a transaction with the bulk
	          insert optimization enabled (with the
	          <a class="xref" href="txnbegin.html#txnbegin_DB_TXN_BULK">
             
             <code class="literal">DB_TXN_BULK</code>
            </a> flag) is in progress,
	          setting the <code class="literal">DB_HOTBACKUP_IN_PROGRESS</code> flag
	          forces a checkpoint in the environment.
	          After
	          this flag is set in the environment, the bulk insert
	          optimization is disabled, until the flag is reset.
	          Using this protocol allows a hot backup procedure to
	          make a consistent copy of the database even when
	          bulk transactions are ongoing.  For more information, see the
	          section on Hot Backup in the <span class="emphasis"><em>Getting Started
	          With Transaction Processing Guide</em></span> and the description of the 
	          <a class="xref" href="txnbegin.html#txnbegin_DB_TXN_BULK">
             
             <code class="literal">DB_TXN_BULK</code>
            </a> flag in the
	          <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a> method.
             </p>
                <p>
	          The <a class="xref" href="db_hotbackup.html" title="db_hotbackup">db_hotbackup</a>
	          utility implements the protocol described above.
	     </p>
              </li>
              <li>
                <p><a id="set_flags_DB_DSYNC_DB"></a>
                  <code class="literal">DB_DSYNC_DB</code>
            </p>
                <p>
                 Configure Berkeley DB to flush database writes to the backing disk
                 before returning from the write system call, rather than flushing
                 database writes explicitly in a separate system call, as necessary. 
                 This is only available on some systems (for example, systems
                 supporting the IEEE/ANSI Std 1003.1 (POSIX) standard O_DSYNC flag, or
                 systems supporting the Windows FILE_FLAG_WRITE_THROUGH flag).  This
                 flag may result in inaccurate file modification times and other
                 file-level information for Berkeley DB database files.  This flag will
                 almost certainly result in a performance decrease on most systems. 
                 This flag is only applicable to certain filesysystems (for example, the
                 Veritas VxFS filesystem), where the filesystem's support for trickling
                 writes back to stable storage behaves badly (or more likely, has been
                 misconfigured).
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_DSYNC_DB flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_DSYNC_DB flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_DSYNC_DB flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_MULTIVERSION"></a>
                  <code class="literal">DB_MULTIVERSION</code>
            </p>
                <p>
                 If set, all databases in the environment will be opened as if
                 DB_MULTIVERSION is passed to the <a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a>
                 method.  This flag will be ignored for queue databases for which DB_MULTIVERSION is not
                 supported.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_MULTIVERSION flag only
                 affects the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle (and any other
                 Berkeley DB handles opened within the scope of that handle). For
                 consistent behavior across the environment, all <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
                 handles opened in the environment must either set the DB_MULTIVERSION flag or the flag
                 should be specified in the 
                 <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_MULTIVERSION flag may be used to configure Berkeley DB at any
                 time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_NOLOCKING"></a>
                  <code class="literal">DB_NOLOCKING</code>
            </p>
                <p>
                 If set, Berkeley DB will grant all requested mutual exclusion mutexes
                 and database locks without regard for their actual availability.  This
                 functionality should never be used for purposes other than debugging.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_NOLOCKING flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle).
            </p>
                <p>
                 The DB_NOLOCKING flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_NOMMAP"></a>
                  <code class="literal">DB_NOMMAP</code>
            </p>
                <p>
                 If set, Berkeley DB will copy read-only database files into the local
                 cache instead of potentially mapping them into process memory (see the
                 description of the <a class="xref" href="envset_mp_mmapsize.html" title="DB_ENV-&gt;set_mp_mmapsize()">DB_ENV-&gt;set_mp_mmapsize()</a> 
                 method for further information).
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_NOMMAP flag only affects the
                 specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle
                 (and any other Berkeley DB handles opened within the scope of that
                 handle). For consistent behavior across the environment, all 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in the
                 environment must either set the DB_NOMMAP flag or the flag should be
                 specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_NOMMAP flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_NOPANIC"></a>
                  <code class="literal">DB_NOPANIC</code>
            </p>
                <p>
                 If set, Berkeley DB will ignore any panic state in the database
                 environment. (Database environments in a panic state normally refuse
                 all attempts to call Berkeley DB functions, returning 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_RUNRECOVERY" class="olink">DB_RUNRECOVERY</a>.)
                 This functionality should never be used for purposes other than
                 debugging.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_NOPANIC flag only affects the
                 specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle
                 (and any other Berkeley DB handles opened within the scope of that
                 handle).
            </p>
                <p>
                 The DB_NOPANIC flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_OVERWRITE"></a>
                  <code class="literal">DB_OVERWRITE</code>
            </p>
                <p>
                 Overwrite files stored in encrypted formats before deleting them. 
                 Berkeley DB overwrites files using alternating 0xff, 0x00 and 0xff
                 byte patterns. For file overwriting to be effective, the underlying
                 file must be stored on a fixed-block filesystem.  Systems with
                 journaling or logging filesystems will require operating system
                 support and probably modification of the Berkeley DB sources.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_OVERWRITE flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle).
            </p>
                <p>
                 The DB_OVERWRITE flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_PANIC_ENVIRONMENT"></a>
                  <code class="literal">DB_PANIC_ENVIRONMENT</code>
            </p>
                <p>
                 If set, Berkeley DB will set the panic state for the database
                 environment. (Database environments in a panic state normally refuse
                 all attempts to call Berkeley DB functions, returning 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_RUNRECOVERY" class="olink">DB_RUNRECOVERY</a>.)
                 This flag may not be specified using the environment's 
                 <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_PANIC_ENVIRONMENT flag
                 affects the database environment, including all threads of control
                 accessing the database environment.
            </p>
                <p>
                 The DB_PANIC_ENVIRONMENT flag may be used to configure Berkeley DB
                 only after the <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>  method is called.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_REGION_INIT"></a>
                  <code class="literal">DB_REGION_INIT</code>
            </p>
                <p>
                 In some applications, the expense of page-faulting the underlying
                 shared memory regions can affect performance.  (For example, if the
                 page-fault occurs while holding a lock, other lock requests can
                 convoy, and overall throughput may decrease.)  If set, Berkeley DB
                 will page-fault shared regions into memory when initially creating or
                 joining a Berkeley DB environment.  In addition, Berkeley DB will
                 write the shared regions when creating an environment, forcing the
                 underlying virtual memory and filesystems to instantiate both the
                 necessary memory and the necessary disk space. This can also avoid
                 out-of-disk space failures later on.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_REGION_INIT flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_REGION_INIT flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_REGION_INIT flag may be used to configure Berkeley DB at any
                 time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="envset_flags_DB_TIME_NOTGRANTED"></a>
                  <code class="literal">DB_TIME_NOTGRANTED</code>
            </p>
                <p>
                 If set, database calls timing out based on lock or transaction timeout
                 values will return 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_NOTGRANTED" class="olink">DB_LOCK_NOTGRANTED</a>
                 instead of 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_DEADLOCK" class="olink">DB_LOCK_DEADLOCK</a>.
                 This allows applications to distinguish between operations which have
                 deadlocked and operations which have exceeded their time limits.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_TIME_NOTGRANTED flag only
                 affects the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle (and any other
                 Berkeley DB handles opened within the scope of that handle). For
                 consistent behavior across the environment, all 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in the
                 environment must either set the DB_TIME_NOTGRANTED flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                The <code class="literal">DB_TIME_NOTGRANTED</code> flag may be used to configure Berkeley DB at
                 any time during the life of the application.
            </p>
                <p>
                Note that the <a class="xref" href="lockget.html" title="DB_ENV-&gt;lock_get()">DB_ENV-&gt;lock_get()</a>
                and <a class="xref" href="lockvec.html" title="DB_ENV-&gt;lock_vec()">DB_ENV-&gt;lock_vec()</a>
                methods are unaffected by this flag.
            </p>
              </li>
              <li>
                <p><a id="envset_flags_DB_TXN_NOSYNC"></a>
                  <code class="literal">DB_TXN_NOSYNC</code>
            </p>
                <p>
                 If set, Berkeley DB will not write or synchronously flush the log on
                 transaction commit. This means that transactions exhibit the ACI
                 (atomicity, consistency, and isolation) properties, but not D
                 (durability); that is, database integrity will be maintained, but if
                 the application or system fails, it is possible some number of the
                 most recently committed transactions may be undone during recovery. 
                 The number of transactions at risk is governed by how many log updates
                 can fit into the log buffer, how often the operating system flushes
                 dirty buffers to disk, and how often the log is checkpointed.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_TXN_NOSYNC flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_TXN_NOSYNC flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_TXN_NOSYNC flag may be used to configure Berkeley DB at any
                 time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_TXN_NOWAIT"></a>
                  <code class="literal">DB_TXN_NOWAIT</code>
            </p>
                <p>
                 If set and a lock is unavailable for any Berkeley DB operation
                 performed in the context of a transaction, cause the operation to
                 return 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_DEADLOCK" class="olink">DB_LOCK_DEADLOCK</a>
                 (or 
                 <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_NOTGRANTED" class="olink">DB_LOCK_NOTGRANTED</a>
                 if configured using the DB_TIME_NOTGRANTED flag).
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_TXN_NOWAIT flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_TXN_NOWAIT flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_TXN_NOWAIT flag may be used to configure Berkeley DB at any
                 time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_TXN_SNAPSHOT"></a>
                  <code class="literal">DB_TXN_SNAPSHOT</code>
            </p>
                <p>
                 If set, all transactions in the environment will be started as if
                 DB_TXN_SNAPSHOT were passed to the 
                 <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a> method, and all
                 non-transactional cursors will be opened as if DB_TXN_SNAPSHOT were
                 passed to the <a class="xref" href="dbcursor.html" title="DB-&gt;cursor()">DB-&gt;cursor()</a> method.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_TXN_SNAPSHOT flag only
                 affects the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
                 handle (and any other Berkeley DB handles opened within the scope of that handle). For
                 consistent behavior across the environment, all 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in the
                 environment must either set the DB_TXN_SNAPSHOT flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_TXN_SNAPSHOT flag may be used to configure Berkeley DB at any
                 time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_TXN_WRITE_NOSYNC"></a>
                  <code class="literal">DB_TXN_WRITE_NOSYNC</code>
            </p>
                <p>
                 If set, Berkeley DB will write, but will not synchronously flush, the
                 log on transaction commit. This means that transactions exhibit the
                 ACI (atomicity, consistency, and isolation) properties, but not D
                 (durability); that is, database integrity will be maintained, but if
                 the system fails, it is possible some number of the most recently
                 committed transactions may be undone during recovery.  The number of
                 transactions at risk is governed by how often the system flushes dirty
                 buffers to disk and how often the log is checkpointed.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_TXN_WRITE_NOSYNC flag only
                 affects the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
                 handle (and any other Berkeley DB handles opened within the scope of that handle). For
                 consistent behavior across the environment, all 
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in the
                 environment must either set the DB_TXN_WRITE_NOSYNC flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_TXN_WRITE_NOSYNC flag may be used to configure Berkeley DB at
                 any time during the life of the application.
            </p>
              </li>
              <li>
                <p><a id="set_flags_DB_YIELDCPU"></a>
                  <code class="literal">DB_YIELDCPU</code>
            </p>
                <p>
                 If set, Berkeley DB will yield the processor immediately after each
                 page or mutex acquisition.  This functionality should never be used
                 for purposes other than stress testing.
            </p>
                <p>
                 Calling <code class="methodname">DB_ENV-&gt;set_flags()</code> with the DB_YIELDCPU flag only affects
                 the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a> 
                 handle (and any other Berkeley DB handles opened within the scope of
                 that handle). For consistent behavior across the environment, all
                 <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handles opened in
                 the environment must either set the DB_YIELDCPU flag or the flag
                 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> configuration file.
            </p>
                <p>
                 The DB_YIELDCPU flag may be used to configure Berkeley DB at any time
                 during the life of the application.
            </p>
              </li>
            </ul>
          </div>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp52051504"></a>onoff</h4>
              </div>
            </div>
          </div>
          <p>
                          If the <span class="bold"><strong>onoff</strong></span> parameter is zero, the
                          specified flags are cleared; otherwise they are set.
                     </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp52018000"></a>Errors</h3>
            </div>
          </div>
        </div>
        <p>
                         The <code class="methodname">DB_ENV-&gt;set_flags()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp52071912"></a>EINVAL</h4>
              </div>
            </div>
          </div>
          <p>
                An invalid flag value or parameter was specified.
            </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp52067824"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
            </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp52075584"></a>See Also</h3>
            </div>
          </div>
        </div>
        <p>
                     <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 
                </p>
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